Black Rock is a location near the Great Valley. Like its name suggests, it is a large black-coloured rock. It is slightly into the Mysterious Beyond. It is featured prominently in "The Hermit of Black Rock" where it is revealed to contain a large cave system.
In the episode, Petrie and Guido were dragged out to Black Rock strong winds when they flew (or in Guido's case glided) too high. They then fell into the caves, where it was revealed Petrie had injured his wing and Guido had injured his foot meaning they couldn't fly/glide out. After wandering for a while, Petrie and Guido found a bush of Ground Stars to eat from (Guido eating the Crawlers living on the bush). There they met Swooper, the titular hermit. Swooper later flew out with them on his back, and despite him being blind and never having flown for many years, he succeeded in taking them back to the Great Valley.
- In some official media, Black Rock is spelled as "Blackrock".
- Besides cave crawlers, there appears to be other creatures living in Black Rock (besides Swooper) owing to the yellow eyes that appeared in 'Don't Be Scared" when Petrie walked by, though maybe these were Petrie's imagination. It is likely, though, that none of them are sentient beings, owning to Swooper not realizing that he was talking to cave columns, something a sentient being would have told him.
- Owing to Petrie and Guido entering at the top and only leaving with Swooper at the top via flight, it it possible that the only entrance to Black Rock is at the top. Thus, it is possible that Swooper flew to Black Rock long ago before being blind, became blind, and ended up stranded there for years, not thinking it safe to fly while blind and alone. It would also explain why Swooper was never bothered by a Sharptooth, if the only entrance was at the top. Further suggesting this theory is the fact that the adults only sent out the Flyers, and not any of the other creatures inhabiting the Great Valley, to retrieve Petrie and Guido, something they probably wouldn't have done, as the adults on the ground wouldn't have been deterred by the blowing wind if there was another entrance to get in. However, the presence of the Sharptooth skeleton in the cave may indicate that there was another entrance, though maybe it is no longer there, perhaps due to a cave in, and the Sharptooth in question died of starvation sometime before Swooper arrived there.
- Other than the dark, it is unknown what made Guido, and to a lesser extent Petrie, afraid of being inside of Black Rock. It is evident, however, that the two had heard about Black Rock before. (This actually is not a given, as, while it can be seen from the Great Valley, so can Saurus Rock, yet the kids never seemed to have heard about Saurus Rock till the sixth movie.)
- Despite it being lit enough for the audience to see in it, there is likely very little light inside of Black Rock, as Petrie and Guido moved slowly inside of it and were afraid around every corner, something that shouldn't have happened had visibility been great inside of there. This theory is even more plausible in that neither of them saw Swooper, even though he had to have been near to have grabbed that Tree Star from Guido.
- It's like their version of the Monolith from 2001: A Space Oydssey.